CORE-15467 - 1st stage setup freezes when the expected file is missing

[Javier Agustìn Fernàndez Arroyo]

An idea,

I don´t think its a good idea to "skip" a file during 1st stage, specially
core files (in 2nd stage it might be acceptable for some device drivers,
for example)

So, if "cloning" the Win2k3 behavior, i would set only 2 options: retry or
abort installation and reboot.

what do you guys think?